[Bug 47167] New: League of Legends launcher displays no content when wine is compiled with gcc-9

https://bugs.winehq.org/show_bug.cgi?id=47167

Bug ID: 47167
           Summary: League of Legends launcher displays no content when
                    wine is compiled with gcc-9
           Product: Wine
           Version: unspecified
          Hardware: x86
                OS: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: -unknown
          Assignee: [e-mail]
          Reporter: [e-mail]
      Distribution: ---

When wine is compiled with gcc-9.1, the League of Legends launcher does not
work. It shows a window with a dark blue background, but no content ever
appears in the window. This makes it impossible to log in and play the game.

When wine is compiled with gcc-8.2, the game works normally

There is only one change to wine's debug output: the following message appears
16 times:
005d:fixme:bcrypt:BCryptOpenAlgorithmProvider algorithm L"\0001" not supported
(I do not know if this is relevant)

Version information:
Wine Staging 4.7
Gentoo
kernel 5.0.7
mesa git
x86_64 cpu